Catalog Home Page

Estimated communication range and energetic cost of bottlenose dolphin whistles in a tropical habitat

Jensen, F.H., Beedholm, K., Wahlberg, M., Bejder, L. and Madsen, P.T. (2012) Estimated communication range and energetic cost of bottlenose dolphin whistles in a tropical habitat. The Journal of the Acoustical Society of America, 131 (1). pp. 582-592.

[img]
Preview
PDF - Published Version
Download (753kB) | Preview
    Link to Published Version: http://dx.doi.org/10.1121/1.3662067
    *Subscription may be required

    Abstract

    Bottlenose dolphins (Tursiops sp.) depend on frequency-modulated whistles for many aspects of their social behavior, including group cohesion and recognition of familiar individuals. Vocalization amplitude and frequency influences communication range and may be shaped by many ecological and physiological factors including energetic costs. Here, a calibrated GPS-synchronized hydrophone array was used to record the whistles of bottlenose dolphins in a tropical shallow-water environment with high ambient noise levels. Acoustic localization techniques were used to estimate the source levels and energy content of individual whistles. Bottlenose dolphins produced whistles with mean source levels of 146.7 +/- 6.2 dB re. 1 mu Pa(RMS). These were lower than source levels estimated for a population inhabiting the quieter Moray Firth, indicating that dolphins do not necessarily compensate for the high noise levels found in noisy tropical habitats by increasing their source level. Combined with measured transmission loss and noise levels, these source levels provided estimated median communication ranges of 750 m and maximum communication ranges up to 5740 m. Whistles contained less than 17 mJ of acoustic energy, showing that the energetic cost of whistling is small compared to the high metabolic rate of these aquatic mammals, and unlikely to limit the vocal activity of toothed whales.

    Publication Type: Journal Article
    Murdoch Affiliation: Centre for Fish and Fisheries Research
    School of Biological Sciences and Biotechnology
    Publisher: American Institute of Physics for the Acoustical Society of America
    Copyright: © 2012 Acoustical Society of America.
    URI: http://researchrepository.murdoch.edu.au/id/eprint/7044
    Item Control Page

    Downloads

    Downloads per month over past year